I'm sorry I'm not directly answring your question. But part of the answer is, that we are not really intending to fix the CO2 issue. A/the major point with the initiative is that we have effectively killed marine/water life in our local rivers, lakes and near coastal areas, primarily by the leakage of fertilizer from low-yield farming areas (algae remove oxygen from our water, having thus killed off marine life). Because of this, we are no longer discussing the economics of it - once you kill off all marine life, the price is 'always' too high (the way we see it..) So, it might help or not help CO2, but our immediate concern is making it possible to have life in our local water bodies, and more oxygen than 0%. I'm describing it a bit crude, but this should paint the general picture. If we run out of food and starve, we can return to killing allmarine life again :-)